Separation of 54 PAHs on an Agilent J&W Select PAH GC Column Application Note Introduction Polycyclic aromatic hydrocarbons (PAHs) are compounds that contain two or more aromatic rings. They are formed during incomplete combustion or pyrolysis of organic matter, industrial processes and cooking and food processing. PAHs are therefore analyzed in environmental and food samples. The difficulty in analyzing PAHs lies in separating PAH isomers. These isomers have the same chemical structure and same ion fragment and therefore cannot be separated by mass spectrometers. The Select PAH capillary column has enhanced selectivity towards PAHs, separating the isomers and enabling accurate PAH analysis. This application note describes an optimized oven program for the Select PAH column. In PAH analysis, there is a difference between the European (EU) and American (EPA) legislation. The legislations both describe a different set of PAHs and address different matrix origins. Table 1 lists the PAH regulated by EU and EPA legislation, including the potential interferences. For this application note, we chose a sample containing 54 PAHs to demonstrate the unique selectivity of the Select PAH. Author John Oostdijk Agilent Technologies, Inc.
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Separation of 54 PAHs on an Agilent J&W Select PAH GC Column · Separation of 54 PAHs on an Agilent J&W Select PAH GC Column Application Note Introduction Polycyclic aromatic hydrocarbons
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Separation of 54 PAHs on anAgilent J&W Select PAH GC Column
Application Note
IntroductionPolycyclic aromatic hydrocarbons (PAHs) are compounds that contain two or more aromatic rings. They are formed during incomplete combustion or pyrolysis of organic matter, industrial processes and cooking and food processing. PAHs are therefore analyzed in environmental and food samples.
The difficulty in analyzing PAHs lies in separating PAH isomers. These isomers have the same chemical structure and same ion fragment and therefore cannot be separated by mass spectrometers. The Select PAH capillary column has enhanced selectivity towards PAHs, separating the isomers and enabling accurate PAH analysis. This application note describes an optimized oven program for the Select PAH column. In PAH analysis, there is a difference between the European (EU) and American (EPA) legislation. The legislations both describe a different set of PAHs and address different matrix origins. Table 1 lists the PAH regulated by EU and EPA legislation, including the potential interferences. For this application note, we chose a sample containing 54 PAHs to demonstrate the unique selectivity of the Select PAH.
AuthorJohn OostdijkAgilent Technologies, Inc.
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ConclusionThe Select PAH column resolves 54 PAHs in a single GC/MS run, including the hard to separate PAH isomers. The optimized GC oven program performs the run time in less than 45 minutes.
ConditionsTechnique: GC/MS, Triple QuadColumn: Select PAH, 30 m x 0.25 mm, df=0.15 µm (part number
CP7462)Sample Conc: approx 0.1-0.3 µg/mLInjection Volume: 1 μL Temperature: 70 °C (0.7 min), 85 °C/min, 180 °C, 3 °C/min, 230 °C (7
min), 28 °C/min, 280 °C (10 min), 14 °C/min, 350 °C (3 min)
Carrier Gas: Helium, constant flow 2 mL/minInjector: 300 °C, Splitless mode, 1 min @ 50 mL/minDetector: Triple Quad, EI in SIM mode, ion source 275°C, transfer
line 300°C
Results and DiscussionFigure 1 shows the separation of all 54 PAH isomers and Figures 2-6 reveal the finer details.
When performing this analysis, there are three sets of peaks that are difficult to resolve. The first set, comprising benzo[a]anthracene, cyclopenta[c,d]pyrene, chrysene and triphenylene, has different masses, m/z 226 and 228. The compounds with m/z 228 also contain some m/z 226, making it difficult to resolve this set by MS alone. The same problem occurs when separating indeno[1,2,3-c,d]pyrene, benzo[b]triphenylene and dibenzo[a,h]anthracene with m/z 276 and 278. The third set of PAH isomers difficult to resolve are the benzofluoranthenes. These three isomers, benzo[b]fluoranthene, benzo[j]fluoranthene and benzo[k]fluoranthene, have the same mass and cannot be resolved by MS.
However, the unique selectivity of Select PAH resolves all the PAH isomers and enables accurate quantification of all PAHs.
Peaks 1 and 2 show some tailing, which can be resolved by further optimization of the splitless injection conditions.
7 154 Acenaphthene X 83-32-98 166 Fluorene X 86-73-79 188 Phenanthrene-d10 1517-22-210 178 Phenanthrene X 85-01-811 178 Anthracene X 120-12-712 202 Fluoranthene X 206-44-013 202 Pyrene X 129-00-014 216 Benzo[a]fluorene 238-84-615 216 Benzo[b]fluorene 243-17-416 216 7H-Benzo[c]fluorene X 205-12-917 234 Benzo[b]naphto[2,1-d]-
thiophene239-35-0
18 226 Benzo[g,h,i]-fluoranthene 203-12-319 228 Benzo[c]phenanthrene 195-19-720 228 Benz[a]anthracene X X 56-55-321 226 Cyclopenta[c,d]pyrene X 27208-37-322 240 Chrysene-d10 1719-03-523 228 Triphenylene 217-59-424 228 Chrysene X X 218-01-925 242 6-Methylchrysene 175-85-726 242 5-Methylchrysene X 3697-24-327 252 Benzo[b]fluoranthene X X 205-99-228 252 Benzo[k]fluoranthene X X 207-08-929 252 Benzo[j]fluoranthene X 205-82-330 252 Benzo[a]fluoranthene 203-33-831 252 Benzo[e]pyrene 192-97-232 252 Benzo[a]pyrene X X 50-32-833 264 Perylene-d12 1520-96-334 252 Perylene 198-55-035 268 3-Methylcholanthrene 56-49-536 330 9,10-Diphenylanthracene 216-105-137 279 Dibenzo[a,h]acridine 226-36-838 279 Dibenzo[a,j]acridine 224-42-039 278 Dibenzo[a,j]anthracene 224-41-940 292 Dibenzo[a,h]
anthracene-d1413250-98-1
41 278 Benzo[b]triphenylene 215-58-742 276 Indeno[1,2,3-c,d]pyrene X X 193-39-543 278 Dibenzo[a,h]anthracene X X 53-70-344 278 Benzo[b]chrysene 214-17-545 278 Picene 213-46-746 276 Benzo[g,h,i]perylene X X 191-24-247 276 Dibenzo[def,mno]-
chrysene191-26-4
48 267 7H-Dibenzo[c,g]-carbazole
194-59-2
49 302 Dibenzo[a,l]pyrene X 191-30-050 302 Dibenzo[a,e]pyrene X 192-65-451 300 Coronene 191-07-152 302 Benzo[b]perylene 197-70-653 302 Dibenzo[a,i]pyrene X 189-55-954 302 Dibenzo[a,h]pyrene X 189-64-0
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Figure 1. GC/MS analysis of EU and EPA PAHs on Select PAH column, 30 m x 0.25 mm x 0.15 µm
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Figure 2. Details and identification of peaks 1 to 8
41 278 Benzo[b]triphenylene 215-58-742 276 Ideno[1,2,3-c,d]pyrene X X 193-39-543 278 Dibenzo[a,h]anthracene X X 53-70-344 278 Benzo[b]chrysene 214-17-545 278 Picene 213-46-7
ReferencesAnon, (2005) Report Joint FAO/Who Expert Committee on Food Additives, Sixty-fourth meeting, Rome, 8-17 February 2005.
Bordajandi LR, et al (2008) Optimisation of the GC-MS conditions for the determination of the 15 EU foodstuff priority polycyclic aromatic hydrocarbons, J. Sep. Sci., 31, 1769-1778.
Lerda D, (2009) Polycyclic Aromatic Hydrocarbons (PAHs) Factsheet. European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, JRC 500871.
Poster DL, et al. (2006) Analysis of polycyclic aromatic hydrocarbons (PAHs) in environmental samples: a critical review of gas chromatographic (GC) methods. Anal. Bioanal. Chem, 386, 859-881.
Ziegenhals K, et al. (2008) Fast-GC/HRMS to quantify the EU priority PAH, J. Sep. Sci., 31, 1779-1786.